sepharose and 3-3--5-5--tetramethylbenzidine

The development of an automated miniaturized analytical system that allows for the rapid monitoring of carbamazepine (CBZ) levels in serum and wastewater is proposed. Molecular recognition of CBZ was achieved through its selective interaction with microbeads carrying anti-CBZ antibodies. The proposed method combines the advantages of the micro-bead injection spectroscopy and of the flow-based platform lab-on-valve for implementation of automatic immunosorbent renewal, rendering a new recognition surface for each sample. The sequential (or simultaneous) perfusion of CBZ and the horseradish peroxidase-labelled CBZ through the microbeads is followed by real-time on-column monitoring of substrate (3,3',5,5'-tetramethylbenzidine) oxidation by colorimetry. The evaluation of the initial oxidation rate and also the absorbance value at a fixed time point provided a linear response versus the logarithm of the CBZ concentration. Under the selected assay conditions, a single analysis was completed after only 11 min, with a quantification range between 1.0 and 50 μg L

Topics: Antibodies, Monoclonal; Armoracia; Benzidines; Carbamazepine; Colorimetry; Enzyme-Linked Immunosorbent Assay; Horseradish Peroxidase; Humans; Microspheres; Oxidation-Reduction; Sepharose; Wastewater

Topics: Animals; Armoracia; Benzidines; Chromatography, Affinity; Chromogenic Compounds; Colorimetry; Horseradish Peroxidase; Humans; Immobilized Proteins; Immunoglobulin G; Mice; Microspheres; Oxidation-Reduction; Saliva; Sepharose; Staphylococcal Protein A

Molybdenum disulfide (MoS2) has attracted increasing research interest recently due to its unique physical, optical and electrical properties, correlated with its 2D ultrathin atomic-layered structure. Until now, however, great efforts have focused on its applications such as lithium ion batteries, transistors, and hydrogen evolution reactions. Herein, for the first time, MoS2 nanosheets are discovered to possess an intrinsic peroxidase-like activity and can catalytically oxidize 3,3',5,5'-tetramethylbenzidine (TMB) by H2O2 to produce a color reaction. The catalytic activity follows the typical Michaelis-Menten kinetics and is dependent on temperature, pH, H2O2 concentration, and reaction time. Based on this finding, a highly sensitive and selective colorimetric method for H2O2 and glucose detection is developed and applied to detect glucose in serum samples. Moreover, a simple, inexpensive, instrument-free and portable test kit for the visual detection of glucose in normal and diabetic serum samples is constructed by utilizing agarose hydrogel as a visual detection platform.

Topics: Benzidines; Blood Glucose; Colorimetry; Diabetes Mellitus; Disulfides; Dose-Response Relationship, Drug; Humans; Hydrogels; Hydrogen Peroxide; Hydrogen-Ion Concentration; Kinetics; Microscopy, Electron, Transmission; Molybdenum; Nanostructures; Nanotechnology; Peroxidase; Sepharose; Temperature